Compressor within motor rotor

ABSTRACT

A compressor comprises a sealed chamber to which a suction pipe and a discharge pipe are communicated, a motor unit fixed in the sealed chamber and consisting of a stator and a rotor for generating rotating force by electromagnetic interaction between the stator and rotor, and a compression unit sucking, compressing and discharging compressible fluid according regular volume change and opening/closing of valve caused by rotating force of the motor unit, wherein the compression unit is disposed in the rotor to miniaturize and lighten the compressor, to reduce input energy of the motor unit, and to reduce vibration noise.

TECHNICAL FIELD

The present invention relates to a compressor using a vane, andparticularly, to a compressor of which a structure is simplified toreduce a volume, weight and production cost of the compressor.

BACKGROUND ART

Generally, a compressor is a device for changing a mechanical energyinto a compressive energy of compressible fluid. And a refrigeratingcompressor can be classified into a reciprocating compressor, a scrollcompressor, a centrifugal type compressor, and a rotary compressor.

Among those compressors, a compressor which reciprocates in acompression space, in which a volume is formed eccentrically, anddivides the compression space into a suction area and a compression areawill be described as follows.

FIG. 1 is a longitudinal cross-sectional view showing an example of thecompressor according to the conventional art, and FIG. 2 is a cutperspective view showing a compression unit of the compressor in FIG. 1.

The compressor shown in FIGS. 1 and 2 was developed and applied toKorean Intellectual Property Office (application No. 10-1999-0042381,date Oct. 1, 1999) by the present applicant, and registered on KoreanIntellectual Property Office at Nov. 14, 2001 (registration No.10-0315954).

As shown in FIGS. 1 and 2, the compressor according to the conventionalart can be classified as the rotary compressor, and comprises: a sealedchamber 10 to which a suction pipe 1 and a discharge pipe 2 areconnected; a motor unit 12 disposed in the sealed chamber 10 to generaterotary force; and a compression unit 14 disposed in the sealed chamber10 to be apart a predetermined distance from the motor unit 12 forsucking, compressing and discharging compressible fluid by the rotaryforce generated in the motor unit 12.

The motor unit 12 comprises: a stator 16 fixedly adhered on an innercircumferential surface of the sealed chamber 10 same as generalelectric motor, and a rotor 18 disposed to maintain a predetermined airgap from an inner circumferential surface of the stator 16 and rotatedby an electromagnetic interaction with the stator 16.

The compression unit 14 comprises: a cylinder assembly 31 disposed inthe sealed chamber 10 for forming a compression space (V) in which thesucked compressible fluid is compressed on outer part; a rotary shaft 20fixed on the cylinder assembly 31 to be rotatable and fixedly adhered toan inner circumferential surface of the rotor to be rotated with therotor 18 when the rotor 18 is rotated; a cam member 23 rotating with therotary shaft 20 as coupled to the rotary shaft 20 and dividing thecompression space (V) in the cylinder assembly 31 into a first space(V1) and a second space (V2); a first vane 60 and a second vane 70contacted to upper and lower sides of the cam member 23 forreciprocating toward inner and outer sides of the compression space (V)along with a cam surface of the cam member 23 when the cam member 23 isrotated and dividing the first and second spaces (V1 and V2) intosuction areas and compression areas respectively.

The cylinder assembly 31 comprises a cylinder 30, and a first and asecond bearing plates 40 and 50 fixed on both sides of the cylinder 30for forming the compression space (V) with the cylinder 30.

The first and second bearing plates 40 and 50 are formed as discs havingpredetermined thickness and area, and comprise: journal portions 42 and52, which are extended and penetrate centers of the discs to havepredetermined heights and outer diameters, having the rotary shaft 20inserted therein to be rotatable, and a first and a second vane slots 44and 54 formed on one sides of the journal portions 42 and 52 for guidingthe reciprocating movements of the first and second vanes 60 and 70.

Herein, the first and second vane slots 44 and 54 are formed as squareholes corresponding to sizes of the first and second vanes 60 and 70from outer circumferences of the first and the second bearing plates 40and 50 toward center sides.

The rotary shaft 20 is formed to have a certain outer diameter and apredetermined length, and consists of a shaft portion 21 inserted intothe first and second bearing plates 40 and 50 and into the journalportions 42 and 52, and a hub portion 22 extendedly formed on one sideof the shaft portion 21 to be coupled to the cam member 23 in thecylinder assembly 31.

The cam member 23 is formed as a disc when it is projected on a plane sothat the outer circumferential surface thereof is slidably contacted tothe inner circumferential surface of the cylinder 30, and is formed as acam surface of sinuous wave having same thickness from the innercircumferential surface to the outer circumferential surface when a sidesurface thereof is projected. And the surface making an top dead center(D1) is rotated as sliding on a bottom surface of the first bearingplate 40, and the surface making a bottom dead center (D2) is rotated assliding on an upper surface of the second bearing plate 50.

The first and second vanes 60 and 70 are formed as square plates, anddisposed to be adhered to the sinuous wave of the cam member 23 in thecompression space (V) of the cylinder assembly 31.

Also, the first and the second vanes 60 and 70 are elastically supportedby an elastic supporting member 90 mounted on the first and secondbearing plates 40 and 50, respectively.

Therefore, the first and the second vanes 60 and 70 respectively dividethe compression spaces (V1 and V2) into the suction areas and thecompression areas as reciprocating up-and-down direction along with theheight of the cam surface of the cam member 23, when the cam member 23is rotated.

Also, a first discharge muffler 46 and a second discharge muffler 56 arefixed respectively on upper side of the first bearing plate 40 and onlower side of the second bearing plate 50, so as to reduce dischargenoise of fluid which is discharged after compressed.

Operations of the compressor according to the conventional artconstructed as above will be described as follows.

First, when the rotary shaft 20 is rotated by the rotating force of themotor unit 12, the cam member 23 coupled to the rotary shaft 20 in thecylinder assembly 31 is also rotated.

At that time, the first space (V1) located on upper part of the cammember 23 is divided into the suction area and the compression area asmaking the top dead center (D1) and the first vane 60 boundaries, andthe second space (V2) located on the lower part of the cam member 23 isalso divided into the suction area and the compression area as makingthe bottom dead center (D2) and the second vane 70 of the cam member 23boundaries.

In above status, the cam member 23 is rotated, and thereby the top deadcenter (D1) and the bottom dead center (D2) of the cam member 23 aremoved and the volumes of the suction areas and of the compression areasof the first and second spaces (V1 and V2) are variable.

At that time, the first vane 60 and the second vane 70 reciprocatetoward opposite directions of each other for the cam surface height ofthe cam member 23.

Therefore, when the top dead center (D1) or the bottom dead center (D2)of the cam member 23 reaches to a discharge starting point after thecompressible fluid is sucked into the respective suction areas of thefirst and second spaces (V1 and V2) simultaneously through the suctionpassage 1 and gradually compressed, at the same time, the compressedfluid is discharged out of the cylinder assembly 31 through dischargepassages (not shown) of the respective compression spaces (V1 and V2).

In addition, the fluid discharged as above passes through the respectivedischarge mufflers 46 and 56 and the sealed chamber 10, and exhaustedout of the compressor through the discharge pipe 2.

On the other hand, another examples of the conventional compressor willbe described with reference to FIGS. 3 and 4 as follows. FIG. 3 is alongitudinal cross-sectional view showing another example of theconventional compressor, and FIG. 4 is a cross-sectional view in lineIV-IV direction of FIG. 3.

As shown in FIGS. 3 and 4, the compressor according to the conventionalart comprises: a sealed case 110 connected to a suction pipe 101 and toa discharge pipe 102, and making an outer case of the compressor; amotor unit 112 comprising a stator 116 fixedly adhered to an innercircumferential surface of the sealed chamber 110 and a rotor 118installed inside the stator 116; and a compression unit 114 for sucking,compressing and discharging compressible fluid by being transmitted therotating force of the motor unit 112.

The compression unit 114 comprises: a cylinder assembly 131 disposed inthe sealed chamber 110 for forming a compression space (V) in which thecompressible fluid which is sucked from outer side is compressed; arotary shaft 120 comprising a shaft portion 121 press-fitted into theinner circumferential surface of the rotor 118 and an eccentric portion122 formed to be eccentric for the shaft portion 121 in the compressionspace (V), coupled to the cylinder assembly 131 to be rotatable androtated with the rotor 118; a cam member 123 connected to an outercircumferential surface of the eccentric portion 122 of the rotary shaft120 to be contacted to an inner diameter of the cylinder assembly 131for rotating and revolving centering around the rotary shaft 120; and avane 160 reciprocating along with a cam surface of the cam member 123for dividing the compression space (V) into a suction area and acompression area.

The cylinder assembly 131 comprises a cylinder 130 and a first andsecond bearing plates 140 and 150 fixed on both sides of the cylinder130 for forming the compression space (V) with the cylinder 130.

A vane slot 144 for guiding the reciprocating movements of the vane 160is formed as cut in the cylinder 130, and an elastic supporting means190 for elastically supporting the vane 160 from outer part of the vaneslot 144 is disposed.

In addition, a discharge passage 185 through which the compressed fluidis discharged is formed on one side of the inner circumferential surfacewhere the cylinder 130 and the first and second bearing plates 140 and150 are contacted.

Also, the first and second bearing plates are formed as disc havingpredetermined thickness and area, and journal portions 142 and 152, towhich the rotary shaft 120 is inserted therein to be rotatable, extendedand penetrated on center portion to have predetermined height and outerdiameter.

Operations of the another example of compressor according to theconventional art will be described as follows.

When electric power is applied to the stator 116 and the rotor 118 isrotated, the rotary shaft 120 which is press-fitted and fixed on theinner circumferential surface of the rotor 118 is rotated so that thecam member 123 coupled to the eccentric portion 122 of the rotary shaft120 is rotated in the cylinder assembly 131 in a state that the cammember 123 is contacted to the vane 160.

In above status, the cam member 123 is rotated, and thereby volumes ofthe suction area and the compression area made by the cam member 123 andthe vane 160 are variable.

Therefore, the compressible fluid is sucked into the compression space(V) of the cylinder assembly 131 through a suction hole 101, andcompressed. In addition, the fluid compressed as above is discharged outof the cylinder assembly 131 through the discharge passage 185, anddischarged out of the sealed chamber 110 through the discharge hole 102.

In the compressor constructed and operated as above according to theconventional art, the motor unit and the compression unit are installedon upper and lower parts with a certain distance therebetween, andtherefore, size of the compressor is increased in length direction andthe cam member is coupled as apart a predetermined distance from thecenter of the rotor, and therefore, the transmission length of therotating force which is generated by the rotor is increased.

That is, as the transmission length of the rotating force is increasedas described above, loss of power is generated, and efficiency of thecompressor for inputted energy into the rotor is lowered.

Also, as the transmission length of the rotating power is increased asabove, the moment of inertia is increased, and accordingly, vibrationnoise of the compressor is also increased.

On the other hand, in order to reduce the moment of inertia on therotary shaft, the journal portions are formed on the first and secondbearing plates for supporting the rotary shaft, however, frictional lossbetween the outer circumferential surface of the rotary shaft and theinner circumferential surface of the journal portions is increased, andthe efficiency of the compressor is also decreased.

Also, the device, in which the compressor is installed, becomes compactand low weight, and production cost is reduced. Accordingly, the size ofthe compressor is also needed to be reduced under same function.However, the conventional compressor is formed long in the lengthdirection, and therefore, a lot of installation space is required forthe compressor.

DISCLOSURE OF THE INVENTION

Therefore, it is an object of the present invention to provide acompressor with a simple structure and a small size by disposing acompression unit in a rotor of a motor unit to make a stator and acylinder assembly a single body.

To achieve the object of the present invention, there is provided acompressor comprising: a sealed chamber to which a suction pipe and adischarge pipe are connected; a motor fixed in the sealed chamber forgenerating a rotating force by an electromagnetic interaction of astator and a rotor therein; a cylinder assembly fixed on an innercircumferential surface of the rotor to rotate with the rotor, forming acompression space therein; a supporting shaft having both ends fixed oninner surface of the sealed chamber to support the cylinder assembly tobe rotatable, a suction passage for supplying fluid into the compressionspace and a discharge passage for discharging compressed fluid; a cammember fixed on the supporting shaft and located on inner side of thecylinder assembly; and a vane fixed on the inner surface of the cylinderassembly to be rotated with the cylinder assembly for sucking the fluidinto the compression space while rotating as adhered to upper and lowersurfaces of the cam member, compressing the fluid, and discharging thefluid through the discharge passage.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a longitudinal cross-sectional view showing an example of acompressor according to the conventional art;

FIG. 2 is a perspective view showing a part of a compression unit in theconventional compressor shown in FIG. 1;

FIG. 3 is a longitudinal cross sectional view showing another example ofthe compressor according to the conventional art;

FIG. 4 is a cross-sectional view in line IV—IV direction in FIG. 3;

FIG. 5 is a longitudinal cross-sectional view showing a compressoraccording to an embodiment of the present invention;

FIG. 6 is a perspective view showing a part of a compression unit in thecompressor shown in FIG. 5;

FIG. 7 is a longitudinal cross-sectional view showing a supporting shaftof the compressor shown in FIG. 5;

FIG. 8 is a cross-sectional view in line VIII—VIII direction in FIG. 7;

FIG. 9 is a cross-sectional view in line IX—IX direction in FIG. 7;

FIG. 10 is a longitudinal cross-sectional view showing a compressoraccording to another embodiment of the present invention;

FIG. 11 is a longitudinal cross-sectional view showing a compressoraccording to still another embodiment of the present invention; and

FIG. 12 is a cross-sectional view in line XII—XII direction in FIG. 11.

MODES FOR CARRYING OUT THE PREFERRED EMBODIMENTS

Hereinafter, preferred embodiments of a compressor according to thepresent invention will be described with reference to accompanyingFigures as follows.

FIG. 5 is a longitudinal cross-sectional view showing a compressoraccording to the present invention, FIG. 6 is a perspective view showinga part of a compression unit in the compressor shown in FIG. 5.

As shown in FIGS. 5 and 6, the compressor according to the presentinvention roughly comprises a sealed chamber 210 to which a suction pipe201 and a discharge pipe 202 are connected, a motor unit 212 disposed inthe sealed chamber 210 for generating a driving force, and a compressionunit 214 inserted into the motor unit 21 for compressing compressiblefluid.

The motor unit 212 comprises a stator 216 fixedly adhered to an innercircumferential surface of the sealed chamber 210, and a rotor 218disposed to maintain a certain air gap with the stator 216 to be rotatedby an electromagnetic interaction with the stator 216.

The compression unit 212 comprises a cylinder assembly 231 fixedlyadhered to an inner circumferential surface of the rotor 218 to berotated with the rotor 218 and form a compression space therein, asupporting shaft 220, which is penetrated by the cylinder assembly 231,having both sides fixed on the sealed chamber 210 to support thecylinder assembly 231 to be rotatable, a cam member 223 coupled to thesupporting shaft 220 in the cylinder assembly 231 for dividing a sealedspace in the cylinder assembly 231 into a first space (V1) and a secondspace (V2), and a first and a second vanes 260 and 270 contacted to bothside surfaces of the cam member 223 and rotated centering around thesupporting shaft 220 by the rotation of the cylinder assembly 231 fordividing the first and the second spaces (V1 and V2) into suction areasand compression areas respectively.

The cylinder assembly 231 comprises a cylinder 230, and a first and asecond bearing plates 240 and 250 fixed on both sides of the cylinder230 for forming the compression space (V) with the cylinder 230.

The first and second bearing plates 240 and 250 are formed as discshaving predetermined thickness and area, and comprise journal portions242 and 252 into which the supporting shaft 220 is inserted. The journalportions 242, 252 penetrate on the center and have predetermined heightand outer diameter. First and second vane slots 244 and 254 arepenetratingly formed on one sides of the journal portions, to which thefirst and second vanes 260 and 270 are slidingly inserted.

Also, it is desirable that the first and second bearing plates 240 and250 form coupling protrusive portions 246 and 256 which are protrudedvertically from an outer circumference of the first and second bearingplates in order to increase contacting area with the innercircumferential surface of the rotor 218. The cam member 223 is formedas a disc when it is projected on a plane so that the outercircumferential surface thereof contacts to the cylinder 230 as slidingon the inner circumferential surface of the cylinder 230, and formed ascam surface of sinuous wave having same thickness from the innercircumferential surface to the outer circumferential surface when theside surface is projected. In addition, when the cylinder assembly 231is rotated, a surface making a top dead center (D1) is slid on the lowersurface of the first bearing plate 240, and a surface making a bottomdead center (D2) is slid on the upper surface of the second bearingplate 250.

The first and second vanes 260 and 270 are formed as square plates, anddisposed to be adhered with the sinuous wave surface of the cam member223 in the compression space (NI) of the cylinder assembly 231. On theother hand, it is desirable that an insulator 237 of cylindrical shapeis disposed between the cylinder assembly 231 and the rotor 218 so thatcompressive heat generated from the cylinder assembly 231 or motor heatgenerated from the rotor 218 can not be transmitted to each other. Theinsulator 237 may be made of a ceramic composite material or othermaterials having the desired insulating properties.

As shown in FIG. 5, the supporting shaft 220 is coupled to both sides ofthe sealed chamber 210 by welding or bolting, and formed to have acertain outer diameter and a predetermined length to support thecylinder assembly 231 to be rotatable.

Also, the cam member 223 is coupled to center portion of the supportingshaft 220, and a suction passage 281 through which the fluid is suckedinto the cylinder assembly 231 and a discharge passage 285 through whichthe compressed fluid is discharged are formed on the supporting shaft220.

Herein, the suction passage 281 is connected to the suction pipe 201when the supporting shaft 220 is coupled to the sealed chamber 210.

Also, the suction passage 281 is formed to be branched to upper andlower directions so as to be communicated with outlets 283 and 284 whichare formed on the first and second spaces of the cylinder assembly 231as penetrating from an inlet 282 of the suction passage 281 to thecenter of supporting shaft 220.

In addition, the discharge passage 285 has inlets 288 and 289 formed onthe first and second spaces near the outlets 283 and 284 of the suctionpassage 281, and an outlet 286 of the discharge passage 285 is formed aspenetrating the upper outer circumferential surface of the supportingshaft 220. Herein, a discharge valve 287 is mounted on the outlet 286 ofthe discharge passage 285 for preventing backflow of the compressedfluid.

As shown in FIGS. 8 and 9, it is desirable that the suction passage 281and the discharge passage 285 are formed parallelly with each otherhaving a certain gap therebetween since the outlets 283 and 284 and theinlets 288 and 289 are formed on same heights as each other and someportions are overlapped in length direction of the supporting shaft 220.

Operations of the compressor according to the embodiment of the presentinvention constructed as above will be described as follows.

First, the cylinder assembly 231 which is fixedly adhered to the innercircumferential surface of the rotor 218 is rotated by the rotatingforce of the motor unit 212. At that time, the cam member 223 is fixedlycoupled to the supporting shaft 220 in the cylinder assembly 231.

In addition, the first and second vanes 260 and 270 which are insertedinto the first and second vane slots 244 and 254 of the cylinderassembly 231 are rotated centering around the supporting shaft 220 bythe rotation of the cylinder assembly 231, and reciprocates along withthe sinuous cam surface of the cam member 223, respectively.

At that time, the fist space (V1) located on upper part of the cammember 223 is divided into the suction area and the compression area asmaking the top dead center (D1) of the cam member 223 and the first vane260 boundary, and the second space (V2) located on lower part of the cammember 223 is divided into the suction area and the compression area asmaking the bottom dead center (D2) of the cam member 223 and the secondvane 270 boundary.

In above status, the cylinder assembly 231 is rotated and the cam member223 is in fixed status, and accordingly, volumes of the suction areasand the compression areas in the fist and second space (V1 and V2) forthe top dead center (D1) and the bottom dead center (D2) of the cammember 223 are variable.

Therefore, the compressible fluid is sucked into the respective suctionareas of the first and second spaces (V1 and V2) through the suctionpassage 281 which is formed as penetrating the supporting shaft 220,gradually compressed, and discharged out of the cylinder assembly 231through the discharge passage 285 formed as penetrating the supportingshaft 220 at the moment when the top dead center (D1) or the bottom deadcenter (D2) of the cam member 223 reaches to a discharge starting point.

In addition, the fluid discharged as above is exhausted to outer side ofthe compressor through the discharge pipe 202 communicated with thesealed chamber 210.

In the compressor constructed and operated as above according to oneembodiment of the present invention, the compression unit is adhered andfixed in the rotor of the motor unit, and therefore, the noise andvibration caused by the moment of inertia on the rotary shaft in theconventional compressor can be prevented.

Also, since the height of the journal portions formed on the bearingplates can be reduced, the frictional area between the supporting shaftand the bearing plate is reduced, and therefore, the functiondegradation of compressor caused by the friction can be prevented.

Also, the compressor according to one embodiment of the presentinvention can be reduced its size in length direction, and therefore,the installation space required by the compressor is reduced. Therefore,the device in which the compressor is installed can be compact and havelow weight.

On the other hand, a compressor according to another embodiment of thepresent invention will be described with reference to FIG. 10 asfollows. Hereinafter, for same components as those of the aboveembodiment, same reference numerals will be used and descriptions forthose will be omitted.

FIG. 10 is a longitudinal cross-sectional view showing the compressoraccording to another embodiment of the present invention.

In the compressor according to the first embodiment of the presentinvention, the cylinder assembly 231 having the compression space (V) inwhich the fluid is compressed comprises the cylinder 230 and the firstand second bearing plates 240 and 250 fixed on both sides of thecylinder 230. However, in the compressor according another embodiment ofthe present invention, an inner space of a cylinder assembly 331 isformed using an inner circumferential surface of the rotor 218 unlike inthe first embodiment.

That is, a first bearing plate 340 and a second bearing plate 350 arefixed on upper and lower sides of the rotor 218 with a certain interval,and thereby the cylinder 230 in the first embodiment can be omitted.

Also, an insulator 337 is disposed between the rotor 218 and thecylinder assembly 331, and thereby, the compression space (V) can beformed by the insulator 337 and the first and second bearing plates 340and 350.

In the compressor constructed as above according to the anotherembodiment of the present invention, the cylinder is omitted and thecompression space (V) is formed using the bearing plates 340 and 350 andthe rotor 218 (more particularly, the insulator 337). Therefore, thenumber of components is reduced less than that of the compressoraccording to the first embodiment, and the structure is simple to reduceproduction cost and to improve productivity.

On the other hand, a compressor according to still another embodiment ofthe present invention will be described with reference to FIGS. 11 and12 as follows.

FIG. 11 is a longitudinal cross-sectional view showing the compressoraccording to still another embodiment of the present invention, and FIG.12 is a cross-sectional view in line XII—XII of FIG. 11.

The compressor according to still another embodiment of the presentinvention comprises a sealed chamber 410 to which a suction pipe 401 anda discharge pipe 402 are communicated, a motor unit 412 fixed in thesealed chamber 410 for generating rotating force, and a compression unit414 received in the motor unit 412 for sucking, compressing anddischarging compressible fluid by being transmitted the rotating forcegenerated by the motor unit 412.

The motor unit 412 comprises a stator fixedly adhered to an innercircumferential surface of the sealed chamber 410, and a rotor 418disposed apart a certain air gap from the stator 416 for generatingrotating force by an electromagnetic interaction with the stator 416.

Herein, the stator 416 may be fixed on the inner circumferential surfaceof the sealed chamber 410 using a method such as welding or bolting.

The compression unit 414 comprises a cylinder assembly 431 fixedlyadhered to the inner circumferential surface of the rotor 418 to berotated with the rotor 418 and having a compression space (V), asupporting shaft 420 having both sides fixed on inner side of the sealedchamber 410, a suction passage 481 and a discharge passage 485 thereinfor supporting the cylinder assembly 431 to be rotatable, a cam member423 coupled eccentrically to an outer circumferential surface of thesupporting shaft 420 and disposed so that one side thereof contacts tothe inner diameter of the cylinder assembly 431, and a vane 460 havingone surface contacted to the cam member 423, rotated centering aroundthe supporting shaft 420 and reciprocated along with a cam surface ofthe cam member 423 to divide the compression space (V) into a suctionarea and a compression area when the cylinder assembly 431 is rotated.

The cylinder assembly 431 comprises a cylinder 430, and a first and asecond bearing plates 440 and 450 fixed on both sides of the cylinder430 to form the compression space (V) with the cylinder 430.

A vane slot 444 is formed as cut in the cylinder 430 for guiding thereciprocating movements of the vane 460, and an elastic supporting means490 for elastically supporting the vane 460 from outer side of the vaneslot 444 is disposed in the cylinder 430.

In addition, the discharge passage 485 through which the compressedfluid is discharged is formed on one side of the inner circumferentialsurface, where the cylinder 430 and the first bearing plate 440 arecontacted, as communicating with the compression space (V).

On the other hand, it is desirable that an insulator 437 of cylindricalshape is disposed between the cylinder assembly 431 and the rotor 418 sothat compressive heat generated from the cylinder assembly 431 or motorheat generated from the rotor can not be transmitted to each other.

The supporting shaft 420 is fixed by welding both sides on the sealedchamber 410 or may be fixed in bolting method.

The suction passage 481 is communicated with the suction pipe 401 whenthe supporting shaft 420 is fixed on the sealed chamber 410, and adischarge valve 487 is mounted on outlet side of the discharge passage485. On the other hand, the cam member 423 can be coupled to thesupporting shaft 420 integrally.

The vane 460 is elastically supported by the elastic supporting member490 fixed on outer circumferential side of the cylinder assembly 431,moved with the cylinder assembly 431 in a state of contacting to the cammember 423 when the cylinder assembly 431 is rotated, and reciprocatedin radial direction of the cylinder assembly 431 along with the camsurface of the cam member 423.

Operations and effects of the compressor according to the still anotherembodiment of the present invention will be described as follows.

First, when the electric power is applied to the stator 416, the rotor418 is rotated by the electromagnetic interaction with the stator 416.

In addition, the cylinder assembly 431 fixedly adhered to the innercircumferential surface of the rotor 418, and the vane 460 elasticallysupported by the outer circumferential surface of the cylinder assembly431 is moved to outer circumferential direction with the cylinderassembly 431.

At that time, the cam member 423 coupled to eccentric portion 422 of thesupporting shaft 420 maintains stopped status in the cylinder assembly431, and therefore, the vane 460 is moved along with the cam surface ofthe cam member 423 to be reciprocated in radial direction of thecylinder assembly 431. Therefore, a volume of the compression space (V)of the cylinder assembly 431 is changed by the cam member 423 and thevane 460, and therefore, the compressible fluid induced into thecompression space through the suction passage 481 is compressed anddischarged through the discharge passage 485.

In addition, the compressible fluid discharged as above is exhausted toouter side of the compressor through the discharge pipe 402.

In the compressor according to the present embodiment, the cylinderassembly having the vane rotates with the rotor to change volumes of thesuction area and the compression area therein, and the vane rotates withthe cylinder to form the compression space for sucking, compressing anddischarging the compressible fluid, as in the compressor according tothe first embodiment.

Therefore, the compressor according to the still another embodiment ofthe present invention is able to obtain the effects of the previousembodiments. In the compressor according to the present invention, thecompression unit is installed in the motor unit to reduce the size ofthe compressor in length direction, and therefore, the installationspace required by the compressor can be reduced and entire size of adevice in which the compressor is used can be reduced.

As the present invention may be embodied in several forms withoutdeparting from the spirit or essential characteristics thereof, itshould also be understood that the above-described embodiments are notlimited by any of the details of the foregoing description, unlessotherwise specified, but rather should be construed broadly within itsspirit and scope as defined in the appended claims, and therefore allchanges and modifications that fall within the metes and bounds of theclaims, or equivalence of such metes and bounds are therefore intendedto be embraced by the appended claims.

1. A compressor comprising: a sealed chamber to which a suction pipe anda discharge pipe are coupled; a motor fixed in the sealed chamber andcomprising a stator and a rotor for generating rotating force by anelectromagnetic interaction between the stator and the rotor; a cylinderassembly fixed on an inner circumferential surface of the rotor to berotated with the rotor, and forming a compression space therein; asupporting shaft having ends fixed on inner surfaces of the sealedchamber to support the cylinder assembly such that the cylinder assemblyis rotatable on the supporting shaft, a suction passage for supplyingfluid into the compression space and a discharge passage for dischargingthe compressed fluid; a cam member fixed on the supporting shaft locatedin the cylinder assembly, wherein the cam member has a circular profilewhen viewed from above or below such that an outer periphery of the cammember is in slidable contact with the cylinder around substantially theentire circumference of the cam member; and at least one vane fixed onthe cylinder assembly to be rotated with the cylinder assembly, whereinthe at least one vane contacts a surface of the cam member as thecylinder rotates to compress and discharge a fluid through the dischargepassage.
 2. The compressor of claim 1, wherein the cam member is formedintegrally on the supporting shaft, wherein the cam member is formed asa disc when it is projected on a plane, wherein the cam member has a topdead center and bottom dead center, and wherein the at least one vaneslides on a surface of the cam member as the cylinder assembly rotates.3. The compressor of claim 2, wherein the at least one vane comprisesfirst and second vanes, and wherein the cylinder assembly comprises: acylinder having an outer side surface fixedly adhered to an innercircumferential surface of the rotor; an upper bearing plate fixed on anupper part of the cylinder having a lower surface constructing thecompression space and a vane slot in which the first vane is inserted;and a lower bearing plate fixed on a lower part of the cylinder havingan upper surface constructing the compression space and a vane slot inwhich the second vane is inserted.
 4. The compressor of claim 3, whereinthe upper bearing plate includes a coupling protrusive portion thatprotrudes up from an outer brim of the upper bearing plate so that anadhering area with the inner circumferential surface of the rotor can beincreased.
 5. The compressor of claim 3, wherein the lower bearing plateincludes a coupling protrusive portion that protrudes down from an outerbrim of the lower bearing plate so that an adhering area with the innercircumferential surface of the rotor can be increased.
 6. The compressorof claim 1, wherein an insulator is disposed between the innercircumferential surface of the rotor and the outer circumferentialsurface of the cylinder assembly so as to reduce heat exchange betweenthe cylinder and the rotor.
 7. The compressor of claim 6, wherein theinsulator is made of ceramic composite material.
 8. The compressor ofclaim 2, wherein the at least one vane comprises first and second vanes,and wherein the cylinder assembly comprises: a cylinder formed as aninsulator to reduce heat exchange between the cylinder assembly and therotor, and having an outer circumferential surface fixedly adhered to aninner circumferential surface of the rotor; an upper bearing platefixedly adhered to an upper surface of the cylinder, having a lowersurface constructing the compression space and a vane slot in which thefirst vane is inserted; and a lower bearing plate fixed on an lowersurface of the cylinder, having an upper surface constructing thecompression space and a second vane slot in which the second vane isinserted.
 9. The compressor of claim 8, wherein the upper bearing plateincludes a coupling protrusive portion that protrudes up from an outerbrim of the upper bearing plate so that an adhering area with the innercircumferential surface of the rotor can be increased.
 10. Thecompressor of claim 8, wherein the lower bearing plate includes acoupling protrusive portion that protrudes up from an outer brim of thelower bearing plate so that an adhering areas with the innercircumferential surface of the rotor can be increased.
 11. Thecompressor of claim 1, wherein the supporting shaft comprises: at leastone suction passage having an inlet coupled with the suction pipe and anoutlet coupled to an inner space of the cylinder assembly; and at leastone discharge passage having an inlet coupled to the inner space of thecylinder assembly an outer penetrating an outer circumferential surfaceof the supporting shaft.
 12. The compressor of claim 11, wherein adischarge valve is mounted on the outlet of the discharge passage forpreventing backflow of discharged fluid.